Turbine



0a. 11, 1938. s. S.ICOOK TURBINE Filed March 11, 1937 INVENTOR MC M ATTORNEYS 0 the mid-length of the Patented Oct. 11, 1938 PATENT OFFICE 2,132,509 TURBINE Stanley Smith land, assignor Cook, Newcastle-on-Tyne, Engto C. A. Parsons and Company Limited, Newcastle-on-Tyne, England Application March 11,

1937, Serial No. 130,348

In Great Britain March 12, 1936 2 Claims.

. The invention relates to elastic-fluid turbine units having ahead and astern sections within a common casing and is an improvement in or modification of the invention described in patent specification, No. 1,885,512.

With the object of eflfecting improvements in such units, the present invention consists in the combinations of elements hereinafter set forth and particularly pointed out in the claims.

The accompanying drawing shows a half longitudinal section through an ahead and astern turbine according to one form of the present invention.

In carrying the invention into effect according to the form shown in the accompanying drawing, the high-pressure ahead turbine, A, is of the reaction type, steam being admitted by the inlet pipe, 2, at one end of the rotor and exhausted by the pipe, 3, at the other end.

The astern turbine, B, of the impulse type is mounted on the same rotor, 4, as the ahead turbine, A, and is disposed within the same casing, 5, at the inlet end of the ahead turbine, the astern steam admission being shown at 6, and the exhaust at I.

The ahead turbine, A, and the astern turbine, B, are divided by a conical diaphragm, 8, packed at 9 in relation to the common rotor body, 4, of the two turbines, the exhaust end of the astern turbine being disposed in proximity to the inlet end of the ahead turbine.

At a point between the diaphragm packing, 9, and the blades of the ahead turbine, a dummy is disposed which consists in general of a cylindrical member, ll, of greater external diameter than the diameter of the diaphragm packing, 9, this cylindrical member being secured to the rotor shaft and rotating within a second cylindrical member, l3, supported in its operative position solely by a conical wall, It, projecting inwardly from a part of the outer casing wall and parallel to the diaphragm, 8, thereby leaving between the diaphragm, 8, and this conical wall, I8, an intermediate space or chamber, F, provided with a flanged branch-piece, 2 l, for connection as by a pipe, 2 la, to a low-pressure point of the range of expansion of the ahead-turbine steam.

In addition, from a point or pocket, 22, at about gland or packing, 9, be-

tween the diaphragm, 8, and the shaft, a duct,

23, is formed in the main casing of the turbine which conveniently runs radially and ends in a facing, 24, a pipe, 24a, secured to which is connected to the condenser, G.

Steam from the operative from reaching the inoperative turbine in view of the packed diaphragm, 9, and connection to the condenser, while the loss entailed by steam leaking past the dummy, when the ahead turbine is operative, is small because the whole axial length of the dummy is effective in preventing leakage.

Variations may be made from the exact structure described without exceeding the scope of the invention.

What I claim is:-

1. An elastic-fluid parallel-flow turbine unit, comprising an ahead turbine and an astern turbine having a common rotor body and a common casing, at least one of said turbines being of the reaction type, the exhaust end of said astern turbine being arranged adjacent the inlet end of said ahead turbine, casing diaphragm means between said ahead and said astern turbines, said means having one wall adjacent the exhaust end of said astern turbine and another wall adjacent the inlet end of said ahead turbine, a packing between each of said walls and said common rotor body and means for connecting an intermediate point of the length of the packing of the former of said walls to a lower-pressure point in the range of expansion of said turbine unit. V

2. An elastic-fluid parallel-flow turbine unit, comprising an ahead turbine and an astern turbine having a common rotor body and a common casing, at least one of said turbines being of the reaction type, the exhaust end of said astern turbine being arranged adjacent the inlet end of said ahead turbine, casing diaphragm means between said ahead and said astern turbines, said diaphragm means having walls extending inwards from said casing and spaced apart axially of said turbines with a chamber therebetween, said diaphragm means including a dummy between said common casing and said common rotor, the whole of the stationary part of said dummy being carried solely by one of said walls, and means for connecting said chamber to a lower-pressure point in the range of expansion of said turbine unit.

turbine is prevented 5 STANLEY SMITH COOK. 

